1. Field of the Invention
The present invention relates to a washing machine.
2. Description of the Related Art
In general, a washing machine is an appliance that washes laundry using surfactant action of detergent, a water stream generated via rotation of a washing tub or a washing blade, shock applied by the washing blade, and the like. The washing machine performs washing, rinsing and/or dehydration processes to remove contaminants adhered to laundry (hereinafter referred to as ‘clothes’) using interaction of water and detergent.
A typical washing machine includes a casing defining an external appearance of the washing machine, an outer tub accommodated in a suspended manner within the casing, and an inner tub rotatably placed within the outer tub. The washing machine further includes a suspension to attenuate vibration when the outer tub vibrates due to rotation of the inner tub and/or a pulsator.
The suspension, typically, is configured to attenuate vibration generated from the outer tub using elasticity/restoration force of a spring, viscosity of a fluid, and the like. However, the suspension may effectively attenuate vibration in a normal state in which the outer tub vibrates with a constant vibration amplitude range, but has difficulty in appropriately dealing with vibration, the amplitude of which is greater than that in the normal vibration state.
In the configuration of the related art, in particular, four corners of the casing are connected respectively to support members, and each support member is connected to the outer tub via the suspension. This configuration is basically intended to deal with vibration of the outer tub in a vertical direction. In the above described related art, as the suspension mounted at four locations attenuates vertical vibration of the outer tub, even horizontal vibration of the outer tub is also attenuated to some extent. However, this is merely a subordinate effect caused by attenuation of vibration in the vertical direction of the outer tub. When horizontal vibration becomes severe, for example, when eccentricity is caused within the inner tub, it is necessary to cease operation of the washing machine.